Dimming headlight-lens.



u. e. CASSADY & L; w. GEORGE.

DIMMING HEADL IGHT LENS. APPLICATION FILED APR- 27. I916.

Patented June 19, 191?.

WITNESSES.-

cLYssns e. C'ASSADY AINDHLAWBENCE w. cnoncn, or rnnmnaronis,

INDIANA,

'ASSIGN ORS TO PRIMOLITE 00. OF INDIANAPOLIS, INDIANA, A CORPORATION OF INDIANA.

Application filed April 27, 1916. Serial No. 93,828.

Headlight-liens, of which the following a specification.

The object of our invention is to .produce a prismatic face for automobile lamps, of such character as of .the light-rays upon a comparatively restricted area of the road a short distance in front of the vehicle and to diffuse the remainder of the light rays both forward and at each side, .the arrangement being such that no distinct glare can reach the eyes of the drivers of oncoming vehicles.

The accompanying drawings illustrate our invention. Figure 1 is an elevation of one face of our device, and Fig. 2 a vertical section, the lamp reflector and source of light being indicated in dotted lines.

In the drawings, 10 indicates a'scries of clear glass prisms which have relatively oblique front andrear faces, the front faces being shown'slanting upward and backward, and the pris'msbeing arranged horizontally with their thin edges upward. -Beneath each. prism 10 is-a horizontal glass section 11, one face 12 of which is ground so as to diffuse all light passing through portion 11. As a convenience in manufacture, portion 11 may be made integral with an adjacent portion 10, and we find it desirable to make the portion 11 prismatic, with' relatively oblique front and rear faces and its thin edgedownward, the front faces of the prisms 11 slanting downward and backward,

or oppositely from the front faces of the prisms 10. The face 13 of the member 10-11 is plain and clear, and the series of I members 1011' are preferably so arranged that all of the plainfaces 13 are. in alinement, although, so far as ultimate efiect is concerned, either side of the prismatic member may be presented to the-source of light without varying the efiect. As a consequence, the structure may be arranged either face out, .and the members 10 11- might be alternated in arrangement, if desired.

In order to extend the arc of'diifused light,-the inclined faces of' the members 10 -11 are arranged outwardly and the ends olfithe middle members are outwardly beveled and left translucent, as indicated at 14:.

. Specification of Letters Patent.

G. CAssADY' to concentrate a portion .Patented'Jull 19, 19M.

' Rays of-light striking the clear surface 13 normally will pass practically .without deflection through thefbody of the sections 10 and 11. The rays which emerge from the clear surface 10' of the member 10 will be deflected away from the normal to said sure face, and will thus be deflected striking the ground a short distance in front downwardly,

of the lamp. The'rays of light which reach the surface 12 will be diffused by the grind ing of saidsurfaceso that said surface becomes-a new source of light from which rays -of light-will radiate in all directions thus producing a diffused light through a spherical arc of 180 horizontally. The rays of light which reach the outwardly beveled surfaces 14 will be diffused at such surfaces, thus producing new sources of light, from which light rays radiate in all directions forward from the planes of such beveled surfaces, and as suchvplanes are outwardly flared with relation to the direction of move-v ment of the car, consequentlythe horizontal segment of the total lens will exceed 180 by twice the angle of bevel of the surfaces 14.

While it is possible and practicable, and

diffused light from the form the screen from a series of sections, as

shown,- these sections being held in proper relationship to each other by 'a suitable frame 15 and cross bars 16. Moreover, the prismatic portions may or may not; be .straight, but may becurved if desired, as

in order'to produce the effect of a general long as the. optical spherical segment, sp prismatic effect described is produced.

We claim as our invention:

1. A glass lamp face compr sing a plurality of transverse clear prismatic portions each havin'ga slanting face, and adjacent interspersed translucent portions, both the prismatic and translucent portions having material lateral extent.

' 2'.-A lass lamp face comprising a plurality o transverseclear prismatic portions each having a slanting face, and a plurality of'adj acent interspersed'oppositely arranged prismatic portions, each having a translucent face.

3AA glass lamp-face comprising a plu-' rality of transverse clear; prismatic portions each having a slanting face, and a plurality of adjacent interspersed'oppositely arranged translucent face.

prismatic portions, each having a translucent face, the ends of some of said portions being outwardly beveled.

' "4:. A lamp glass comprising a plurality of transverse c ear prismatic portions each having a slanting face,and a plurality of interspersed oppositely placed prismatic portions, one face of each of such last-mentioned portions being ground and translucent.

5. A lamp glass comprising a plurality of transverse clear prismatic portions each having a slanting face, and a plurality of interspersed prismatic portions, one face of each of 'such last-mentioned portions being. ground and translucent.

6. The combination with a lamp and its casing, of a lass face therefor comprising a. plurality of clear transverse prisms with their thin edges upward, and a plurality of interspersed prisms with their thin edges downward and one face translucent and outwardly beveled translucent ends. L A

7. The combination with a lamp andits casing, of a glass face therefor comprising a plurality of clear transverse prisms with their thin edges upward, and a plurality of interspersed prisms with their thin edges downward and one face translucent. 1 1

8. The combination with a lamp and its casing, of a glass face therefor, said glass face comprising a plurality of transverse sections, the upper portion of each of which is prismatic with its thin edge upward, and the lower portion of which is prismatic with its thin edge downward and provided with one translucent face.

9. The combination with a lamp and its casing, of a glass face therefor, said glass face comprising a plurality of transverse sections, the u per'portion of each of which is rismatic .wlth its thin edge upward, and the ibwer portion of which is provided with one 10. The combination with a lamp and its casing, of a glass face therefor, said glass face comprising a plurality of transverse sections, the u per portion of each of which is prismaticwith its thin edge upward, and the ower portion of which is prlsmatic with its thin edge downward and provided with one translucent face, the middle sections having their ends outwardly beveled and translucent. v

11. The combination with a lamp and its casing, of a glass face therefor, said glass face comprising a plurality of transverse sections, the u per. portion of each of. which is prismatic W1th its thin edge upward, and the lower portion of which is provided with one translucent face, the middle sections having their ends outwardly beveled and translucent.

12. A glass lamp face formed of a plurality of transverse glass sections, a portion at one edge being clear and prismatic, with the thin portion of the prism at the edge, and

theirem'aining portion of which has a ground face.

.. 13. A glass lamp face formed of a plurality of transverse glass sections, a portion at one edge being clear and prismatic, with the thin portion of the prism at the edge,

and the remaining portion of which has a I ground face, said ground face being beveled, with the thin portion at theother edge of the section.

14:. A glass lamp face formed of a plurality of transverse glass sections, a portion at one edge being clear and prismatlc, with the thin portion of the prism at the edge, and the remaining portion of which has a ground face, the outer ends ofthe middle sections being outwardly beveled and having ground faces.

15. A glass lamp face formed of a plu-. rality of transverse glass sections, a portion atone edge being clearand prismatlc,

with the thin portion of the prism at the edge, and. the remaining portion of which has a ground face, said'ground face being beveled, with the thin .portion at the other edge of the section, the outer ends of the 17. A lamp glass, comprising a plurality of horizontally extending clear prismatic portions having their front and rear faces at an oblique vertical angle to each other, said clear portions being thinner at the top, and a plurality of interspersed'translucent portions, said translucent portions having ground surfacesin a plurality of planesso that a diffused light is obtained through a greater are than 180.

18. A lamp glass, comprising a plurality of interspersed clear and translucent portions, said clear portions comprising horizontally extending prisms which are thinner at the top and have front and rear faces which are at a relatively oblique vertical angle to each other.

In witness whereof, we have hereunto'set our hands at Indianapolis, Indiana, this twenty-second day of April, A. D. one thousand nine hundred and sixteen.

' ULYSSES G. CASSADY.

LAWRENCE W. GEORGE. 

